US calorie calculator

[wheezing donkey]

I was also surprised by the estimation of calories used. It's over 100 calories per 8-minute flat mile for someone weighing 135lbs. That seems way too high to me.

IIRC, the figure of 100 calories burned per 8 minute mile was quoted by Jim Fixx in "The Complete Book of Running", published back in '77. That book was a huge inspiration to me, back in the day.

[noel]

IIRC, the figure of 100 calories burned per 8 minute mile was quoted by Jim Fixx in "The Complete Book of Running", published back in '77. That book was a huge inspiration to me, back in the day.

Intriguing. Does anyone know the science behind these calculators?

If I run 5 miles on the flat at a gentle pace, presumably I should be eating an extra 550(ish) calories to fuel the run - irrespective of how quickly I run it??
Plus some extra calories on top of that for those hours after the run during which my metabolism is at a higher rate. Or is that taken into account in the above?